Micro-and nano-celluloses derived from hemp stalks and their effect as polymer reinforcing materials

Fiber-reinforced polymers have emerged as one of the most popular methods to improve the polymers' char-acteristics owing to their prominent properties. This study aimed to investigate the properties of cellulose mi-crofibers (CMF), cellulose nanocrystals (CNC) and cellulose nanofibrils (CNF) extracted from hemp stalks, then their effect as reinforcement for the PVA-polymer. CMF have been extracted from hemp stalks with a diameter and yield of 16.96 mu m and 63 %, respectively. Needle-shaped CNC were obtained from CMF using sulfuric acid hydrolysis at two hydrolysis times, while CNF exhibited a web-like structure obtained using TEMPO-oxidation followed by mechanical treatment. Cellulose derivatives were utilized to develop cellulose-based PVA compo-sites; their transparency, chemical structure, thermal stability and mechanical properties were investigated. The incorporation of nanocellulose demonstrated a significant increase in mechanical properties compared to the neat PVA. The extracted nanocellulose could be used as nanofillers for the preparation of transparent and me-chanically strong PVA-based nanocomposites.